The present invention is directed to a lighting fixture for use in medical operations and therapeutic treatment. More particularly, the present invention is directed to such a lighting fixture which has a plurality of individual lamps arranged within a lamp housing and which is capable of having the focus thereof adjusted. The present invention permits adjustment of the position of the lamp housing and the focal point of the lamps to be simultaneously done by a simple single manipulation of the lighting fixture by means of a single lever. Further, a transformer is located in a balanced position within the housing so that the light intensity of each lamp can be adjusted by manipulation of a control lever on the side of the lamp housing.
Previous devices of the above-described type have been inefficient to operate in that an extra person is required to adjust the lighting fixture for the person performing the medical operation or therapeutic treatment. Specifically, devices of the prior art are shown in FIGS. 1 through 3 and are characterized in that they are suspended from a ceiling 1 by an arm 2 which includes three parts so as to be universally movable about the point where it is attached to the ceiling. Further, as shown in the prior art drawings, the lower end of arm 2 has a lamp housing supporting arm 3 attached thereto for tilting about its axis and swinging in the vertical direction.
The supporting arm 3 has a lamp housing 4 attached thereto for tilting which holds a plurality of lamps 5 concentrically arranged therein. At the center is located a step down transformer 6 and a rotating member 7 which covers the transformer 6. The lamps are connected to the periphery of the plate 7 by transmission rods 11 through universal joints 9 and pivot points 10 whereby each lamp 5 can be adjusted by rotation of the rotating plate so that individual beams of light intersect at a desired focal point. A gear 12 is attached to the member 7 and meshes with another gear 15 which is fixedly secured to one end of a rod 14 which extends through, and out the side of the lamp housing with a knob 13 attached to the other end of the rod 14, outside of the lamp housing, for adjusting the lamps 5 as previously described. In prior art type devices, there is also a handle 16 located on the inside and half way down the side of the lamp housing which is used for adjusting the height or angle position of the lamp housing while the knob 13 must be turned to adjust the lamps 5.
Thus, in the conventional lighting fixtures of the kind as previously described, a disadvantage is that there are required two persons to use the lighting fixture since the person who is doing the medical operation or treatment, usually a doctor, must refrain from touching the handle and knob, which may not be sterilized, in order to prevent microbes from entering the area being treated and creating a secondary infection therein.
Other disadvantages inherent in the prior art type devices is that the use of a second person for continually adjusting the lighting fixture results in much time and labor being lost, especially if that person is a nurse and the doctor has to be continually instructing her about the lighting angle and focus to achieve optimum lighting.
If the lighting adjustment by the nurse is not adequate, it may result in unduly tiring the doctor's or treating person's eyes and as a result, the operation or treatment may turn out to be unsuccessful.
Generally two separate adjustments of lighting fixtures of this kind, as described above, are required. The reasons for this are that the lighting fixture must be as compact as possible while at the same time illuminate a specific area with an appropriate intensity light for the particular circumstances for which the lamp is being used. This being the case, a multiple adjustment lamp, i.e. adjustment for intensity, focus and position, cannot be avoided. It therefore becomes very important to combine the position or mechanical adjustment mechanisms into one single mechanism which allows a single person to use the lamp while performing medical operations or therapeutic treatment and which up to now, has not been shown in the prior art.